use anybusiness process modeling tool to model this scenario

When a claim is received, it is first registered. After registration, the claim is classified leading to two possible outcomes: simple or complex. If the claim is simple, the insurance policy is checked. For complex claims, both the policy and the damage are checked independently. A possible outcome of the policy check is that the claim is invalid. In this case, any processing is canceled and a letter is sent to the customer. In the case of a complex claim, this implies that the damage checking is canceled if it has not been completed yet. After the check(s), an assessment is performed which may lead to two possible outcomes: positive or negative. If the assessment is positive, the garage is phoned to authorize the repairs and the payment is scheduled (in this order). In any case (whether the outcome is positive or negative), a letter is sent to the customer and the process ends. At any moment after the registration and before the end of the process, the customer may call to modify the details of the claim. If a modification occurs before the payment is scheduled, the claim is classified again (simple or complex) and the process is repeated. If a request to modify the claim is received after the payment is scheduled, the request is rejected.